ANTIGENS AND ANTIBODIES 23 



treated is said to be " sensitized," i.e., its cells have pro- 

 duced an excess of antibodies against the particular 

 foreign material introduced. 



Anaphylaxis 



Anaphylaxis is the term given by Richet to a state 

 of hypersusceptibility or supersensitiveness to the ac- 

 tion of a foreign protein, after the animal has been 

 first " sensitized " by an injection of the protein in 

 question. The phenomena of anaphylaxis will be 

 discussed in greater detail in Chapter IV. 



